ETIOLOGY AND PATHOGENESIS OF PAIN IN RHEUMATIC DISEASES

Upalne reumatske bolesti karakterizira kronična upala s ozljedom tkiva i nakupljanjem upalnih stanica. Pri oštećenju i upali sintetiziraju se i otpuštaju brojne tvari (kao što su ioni vodika, adenozin trifosfat i bradikinin), koje mogu uzrokovati bol podražajem specijalnih vlakana osjetnoga živčanog sustava – nociceptora, ili mogu uzrokovati preosjetljivost nociceptora na sljedeće i blaže podražaje koji u običnim okolnostima ne uzrokuju bol (prostaglandin E2 i bradikinin). Akutna upala ima zaštitnu ulogu jer uzrokovanjem boli nastaje poštedno ponašanje i imobilizacija koja omogućuje cijeljenje. Međutim, ako upala traje dugo, nastaju funkcionalne, potom i strukturne promjene osjetnoga živčanog sustava u obliku periferne i centralne senzitizacije koje mogu uzrokovati kroničnu bol i patnju, a ozljeda koja je uzrokovala bol često više i nije prisutna. Navedeno je važno jer kronična bol uzrokuje fi zičku onesposobljenost, brojne psihičke promjene, kao što su anksioznost i depresija, te utječe na kvalitetu života. Iz navedenoga je vidljiva važnost razumijevanja etiologije boli, liječenja akutne boli i upale, a ako bol potraje, razumijevanjem etiologije kronične boli možemo ju uspješnije liječiti i spriječiti nepotrebnu patnju bolesnika.Rheumatic diseases are chronic infl ammatory disorders with ongoing infl ammation that causes tissue damage. Infl ammatory and damaged cells synthetize and release many diff erent intracellular substances which can activate highly specialized subsets of primary sensory neurons called nociceptors. Some of these proinfl ammatory mediators directly activate the nociceptor terminal and produce pain (such as hydrogen ion, adenosine triphosphate, and bradykinin), and others sensitize the terminal so that it becomes hypersensitive to subsequent and non-noxious stimuli (such as prostaglandin E2 and bradykinin). Acute pain has a protective role since it induces behavior that promotes healing and recovery, such as immobilization which limits tissue damage. Chronic pain is unhelpful pain that tends to be out of proportion to the actual tissue damage and persists long aft er the tissues have healed, so that the pain becomes the problem rather than the tissues of origin. Chronic pain aff ects the physical and mental status and causes impairment of quality of life as well as work disability. For rheumatologists the assessment and treatment of pain is a very important integral part of patient care, and understanding the etiology and pathogenesis of pain is necessary to fi nd adequate modalities of treatment to prevent suff ering